Author(s):
The aim of this study is seasonal changes in dementia mortality in Japan and to pursue the excess death on COVID-19. From the monthly death from dementia (G30, Alzheimer disease, F01-03, Vascular Dementia and Other) extracted from the vital statistics in Japan from 2019 to 2020, the dementia mortality rate by sex-age group aged 65 and over was obtained. Dementia mortality did not differ significantly between 2019 and 2020, so excess mortality from COVID-19 infection could not be detected. However, the mortality rate has been on a slight upward trend since October 2020. Since autumn, an increase in mortality has been observed in the elderly aged 80 and over, compared to the mortality rate in the 65-79s. The existence of obvious excess deaths could not be proven. On the other hand, we suggested that there was an increase in dementia mortality among people aged 80 and over in Japan, which coincided with the time of the COVID-19 epidemic. Excess mortality from dementia could not be detected in 2020, but an increase in mortality was observed in the age group over 80 years old from the autumn.